[Bug rtl-optimization/54300] [4.7, 4.8 Regression] regcprop incorrectly looks through parallel register swap operation

[rearnsha at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54300

--- Comment #16 from Richard Earnshaw <rearnsha at gcc dot gnu.org> ---
Author: rearnsha
Date: Thu Jan  9 15:18:55 2014
New Revision: 206466

URL: http://gcc.gnu.org/viewcvs?rev=206466&root=gcc&view=rev
Log:
    PR rtl-optimization/54300

gcc:
    * regcprop.c (copyprop_hardreg_forward_1): Ensure any unused
    outputs in a single-set are killed from the value chains.

gcc/testsuite:
    * gcc.target/arm/pr54300.C: New test.

Added:
    branches/gcc-4_8-branch/gcc/testsuite/gcc.target/arm/pr54300.C
Modified:
    branches/gcc-4_8-branch/gcc/ChangeLog
    branches/gcc-4_8-branch/gcc/regcprop.c
    branches/gcc-4_8-branch/gcc/testsuite/ChangeLog